Honda Automobiles HRM215 Harmony Owner's Manual page 55

MAINTENANCE & ADJUSTMENTS
4. Measure the spark plug
electrode gap with a feeler
gauge. The gap should be
0.7 - 0.8 mm (0.028 - 0.031
0.7-0.8
mm
in). Correct the gap, if
(0.028-0.031
in)
necessary, by carefully
bending the side electrode.
5. Install the spark plug carefully,
by hand, to avoid
cross-threading.
6. After the spark plug seats,
tighten with a 20.6 mm (13/16
in) spark plug wrench to
compress the washer.
If reinstalling the old spark
plug, tighten l/8 to l/4 turn
after the spark plug seats.
If installing a new spark plug,
tighten l/2 turn after the spark
plug seats to compress the
washer.
1 NOTICE 1
A loose spark plug can overheat and damage the engine.
Over-tightening the spark plug can damage the threads in the
cylinder head.
7. Install the spark plug cap on the spark plug.